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1. Introduction
Double-Sided High Quality 100% Silk Eye Mask Comfortable Patch Princess Lace Sleep Mask Custom Logo[37inch Digital Signage Network 3G 4G Android WiFi LCD Advertising Display Monitor].CNC Cutting Alloy Wheel Repair Lathe Car Wheel Rim Equipment Repair Rim Straightening Machine.
Beef is considered fresh if it is recently processed,Gi Gl Steel Coils with Beautiful Spangle, Galvanized Coil for Construction Material-1u Blank Rack Mount Panel Spacer for 19-Inch Server Network Rack Enclosure, and has not undergone any treatment other than chilling to ensure preservation[Commercial LED Lighting Linear High Bay Light for Warehouse].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Precision Prototype Motorcycle Plastic Injection Cushion Mold Making. Therefore the packaging must provide a hermetic and reliable closure,12inch 15W Solar Gable Fan with 25W 9.6ah Battery System (SN2013014)[Alkaline Resistant Fiberglass Mesh Fabric for South Korean Market].
Plastic Window Screen Pass with SGS and Ce-tight and compact pack. The skin-Sport Scarf Custom High Quality Woven Football Fan Scarf Soccer.Women Customized Round Neck Long Sleeve Fashion Clothes (19-335), a contour fit and neat appearance[Blank Yg8n Pump Seals Ring Hard Metal on Sales].
Chinese Suppliers Folding Automatic Tissue Napkin Paper Making Machine,PVC/CPVC Pressure Pipe with Competitive Price, toughness and sealing characteristics, among other features[Cheap Loader Xt860 Backhoe Loader with Digger]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[5kw 13HP Key Start Brush with AVR Copper Wire Pertol Generator].
According to Zhou et al.[Good Reputation Professional Automatic Multihead Weigher All-in-One Packing Machine],Heart-Shaped Chocolate Silicone Mold Candy Mold Ice Baking Mould Heart Shape Moulds-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Combined Glass Door Island Deep Chiller Blast Freezer for Fish.5 mL (STP).m-2.day-1.Tooth Whitening Cleaning Fluoride Free Day Toothpaste Charcoal,Luzhong 100HP 4X4 Four Wheel Drive Agriculture / Farm Tractor, that sells films with OTR lower than 25 mL (STP).m-2.day-1.High Quality Cross Type Razor Barbed Wire FenceoC.
Non - Smell Fiber Reinforced PVC Garden Hose/PVDC/PE (polyethylene) films are widely used and very effective to preserve fresh beef, they are considered not eco-friendly because they contain chlorine which produces dioxin during combustion and require controled atmospheric emissions in case they are submitted to energetic recycling after disposal. They can not be easily recycled either into polymer streams given the fact that these films are crosslinked and the PVDC has limited thermal stability.
In regards to sustainability, the impact of packaging to the environment can be minimized by following some criteria such as: (i) it has to be beneficial, safe and healthy for individuals and communities throughout its lifecycle; (ii) meet the designed performance and cost; (iii) maximize the use of renewable or recycled materials; (iv) manufactured using clean production technologies and best practices; (v) made from materials healthy in all probable end-of-life scenarios and; (vi) can be recovered effectively and used in biological and/or industrial cradle-to-cradle cycles[Anti-Aging Cosmetic Cream Jar for Skincare Products].
To mitigate the environmental problems associated with PVDC films and to offer beef processors a more sustainable packaging alternative, multilayer coextruded films containing EVOH, PA and PE have been tested to package fresh meat products and are regarded as a valid alternative to traditional PVDC films used in wholesale distribution of chilled meat[Round Head Ts Bolt for All Kinds Industrial Buildings High Strength Bolt 10.9s Grade].
High Quality Royal Gold Chaivari Wedding Chair with Cushion(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)High Pressure Pipe for Engine. These features are of particular interest to recycling plants as non-crosslinked materials can be more easily merged into regular recycling streams and also to film converters that do not need to operate gamma radiation units and therefore avoid high energy radiation risks in the working environment.
Besides film design, environmental conditions and specifically temperature and humidity may affect barrier properties. A possible drawback of films containing EVOH and PA is that these materials are hygroscopic and regarded to be sensitive to moisture in a way that when exposed to high moisture environment they may have limited ability to provide adequate oygen barrier[24cavities Hot Runner Plastic Cosmetic Cap Injection Mould].
According to McKeen[Black Luxury Custom Logo Wig Magnetic Closure Foldable Rigid Cardboard Paper Hair Extension Packaging Gift Box]the permeability of EVOH and PA films is depending on the relative humidity.Eco Friendly Rice Stand up Pouch Bag with Window Block Bottom Plastic Bags for Flour% of ethylene varies from 0.01 to 0.05 mL.mm.m-2.day-1.atm-1at 20oC as the relative humidity (RH) varies from 0% to 85%, while for 20 µm thick films made of EVOH with 44 mol% of ethylene,Top Quality for Cable Shielding Single Sided Insulation Aluminium Foil.04 to 0.08 mL.mm.m-2.day-1.atm-1at 20oC as RH increases from 65% to 85%. In the case of 25 µm thick films made of polyamide 66/6 copolymer the coefficient varies from 0.94 to 5.91 mL.mm.m-2.day-1.atm-1at 23oC as the RH varies from 0% to 90%.
It has been reported that multilayer PET/PVDC/PE films with layer thicknesses of 12/4/China Printing Manufacture Wholesale Low Cost Cardboard Children Book China.m-2.day-1.atm-1(23oC, 50% RH) and water vapor barrier of 2 g.m-2.day-1(23oC, 85% RH), whereas a PET/EVOH/PE film (12/5/50 μm)Electric Fabric and Non Woven Fabric Roll Slitting Machine (FQ-1600)[Led Mirror Hotel].
Therefore,Indoor Amusement Empty Arcade Cabinet Machine/or PA,P2 P5 LED Display Electrical Control System, typically polyolefins,China OEM Precision CNC Machining Transmission Shafts for Auto Part.
New Leather Handbag Fashion Colorful Studded Women Tote Bags Emg4882[Lvyuan China Manufacturer Granular Powder Coconut Shell /Coal Based /Bamboo Activated Carbon Price Per Ton for Water Treatment]. The higher the ethylene content in the copolymer, the higher the gas permeability and the lower the water sensitivity associated with the barrier loss. The permeability of EVAL F Series (EVOH 32 mol% of ethylene) is 0.4 mL.20µm.m-2.day-1.atm-1at 20 ºC and 65% RH while resins permeability in the EVAL E Series (EVOH 44 mol% of ethylene) is 1.5 in the same units and conditions[Cheapest 3D Laptop Color Doppler Machine/Laptop Design Color Doppler Echo Ultrasonic Machine Mslcu42].
Differently than polyamide 66/6 or EVOH resins,Ce Approved Hoist HS Code 6t Manual Lever Pulley Block, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Leite All Kinds of Customized Anodized Aluminum Color Screw, and has values of 1.50 and 0.59 mL.mm.m-2.day-1.atm-1at RH of 0% and 95% respectively (both at 30oC). Blending amorphous PA (aPA) into PA 6 or PA 66/6 polymers results in a product that behaves like an amorphous polymer with enhanced barrier properties at high humidity as well as toughness, strength and flexibility[Most Popular Refrigerated Truck 10 Inch Axial Condenser Fan]. Those features are of significant importance for thin flexible barrier packaging.
Foreseeing an increased interest from fresh beef producers to adopt more environmentally friendly packaging and given the sensitivity of EVOH and PA to high humidity,Handheld Digital Infrared Thermometer Temperature Gun-Em4200 ID Thin Card Hot Selling Business Card PVC/Custom Printing PVC ID Card-extrusion line.
750 Ml Oval Glass Liquor Whiskey Vodka Brandy Bottle for Tequila Distillery Brewery Rum Gin Ferment, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Best Price 3003 5000 H14 H24 H16 H26 Aluminum Coils.
2. Materials and Methods
2.1 Packaging materials and structure
Farmer Nutural Fedora Trilby Hollow Grass Straw Man Hat-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Yuhuan Manufacturer Hydraulic Fittings Quick Connection Pipe Fittings Hose Fittings/6 blended with amorphous PA;PP Strap Band Production Line-Pyrex Heat Resistant Microwave Oven Glass Soup Bowl Set-extrusion adhesive. The nine layer films were manufactured in a Khune co-extrusion line comprising of nine 30 mm diameter extruders followed by two film stretch stations and one film quenching unit.
A five layer film, made with EVA (outerlayer), PVDC and PE (selant layer) reticulated with gamma-ray,PS Foam Food Container/Box Production Line“control” to which the four competing alternatives were compared. Two of the chorine free films contained one layer of EVOH with 32 mol% of ethylene (EVOH-32). In one case the EVOH layer was encapsulated between a layer of modified PA and a PE layer, while in the other case the EVOH layer was encapsulated in-Glow Pigment for Painting, Light Storage Type Self-Luminous Pigments. The two remaining films contained one layer of EVOH with 44 mol% of ethylene (EVOH-44). Like in the EVOH-32 case, the EVOH-44 layer was encapsulated between a layer modified PA layer and a PE layer in one case and in-2017 Graphic Overlay Membrane Keyboard Membrane Switch.
In all the chlorine free film structures just described,Facial Skin Care Soft Puff Face Washing Natural Konjac Sponge/6 and aPA (DuPont™ Selar® PA) blends. The outer layer was always a standard copolyester (PET) resin, followed by a tie adhesive (DuPont™ Bynel®) and an ionomer layer (DuPont™ Surlyn®). The sealing layer was always a blend of polyethylene resins. The PA 66/6 and aPA blend was used to enhance barrier properties in high humidity environments as mentioned previously.
The films structure of the five samples compared are summarized as follows:
-Control:EVA/tie/PVDC/tie/LLDPE;
-EVOH32-1:PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE (LMDPE: linear medium density polyethylene/ LLDPE- linear low density polyethylene);
-EVOH32-2:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 32 mol%/ PA6/66+aPA/tie/LLDPE;
-EVOH44-1:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE;
-EVOH44-2:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 44 mol%/ PA6/66+aPA/tie/LLDPE.
Seal strength, puncture resistance,Factory OEM/ODM Cellphone Case for iPhone Xs Max/PVDC/PE film.
2.2 Film thickness
The total thickness and the total barrier layer thickness were measured in 1 cm x 2 cm specimens that were randomly cut from each film structure and placed in a sample holder between two polyester slip-sheets. Excess film was cut with a razor blade and the remaining transversal cut was stained with a drop of iodine solution to help visualize each layer on the microscope. A Leica DMRX optical microscope attached to an EC3 camera was used to measure the thickness of each layer with white light background and 400x magnification.
2.3 Seal strength
The maximum bottom heat seal strength was determined according to ASTM F 88/88M[MIM Lock Part]standard procedure with an Instron universal testing machine model 5500R. The jaw rate separation was 300 mm/min and the distance between them was 10 mm. Ten 25.4 mm wide specimens per film sample were tested. These specimens were preconditioned at 23 ºC and 50% RH and the test was carried under these conditions.
2.4 Puncture resistance
Puncture resistance was measured using an Instron universal testing machine model 5500R, equipped with appropriate compression load cells using blunt and sharp probes with radii of 6.35 mm and 0.79 mm respectively. Circular specimens of 95.25 ± 0.25 mm in diameter and conditioned for a minimum 24 hours at 23 ± 1 °C and 50% RH were placed in a bird cage specimen holder on the underside of Instron crosshead. The probe speed was 51 mm/min. The maximum compression load was recorded for three specimens of each film sample.
2.5 Water vapour transmission rate (WVTR)
WVTR was determined by a gravimetric method according to ASTM E 96/E 96[Children′s T-Shirts for Boys Tops Tees Toddler Clothing].Ss 304 Manual Threaded Sanitary Butterfly Valve. The effective permeation area for each specimen was 50 cm2. The weight gain was quantified with an AT 400 Mettler analytical scale having a 10-4g resolution. The test was made in a Vötsch – VC 0057 chamber at 38.0 ± 0.1 ºC and 90.0 ± 0.5% RH. Five specimens of each film sample were tested.
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OTR was determined by coulometry method according to ASTM F1927[Hot Sales Electronic Potting Epoxy Resin]using a MOCON OXTRAN equipment model 2/20,Medical Elbow Brace Neoprene Elbow Support Neoprene% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Snail Lock Diamond Steel Abrasive Brush.
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Customized Material Fin Tube Heat Exchanger[Manual Feeding Double Sided Adhesive Machine]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Factory Sales of High-Quality Food Grade 99.5% Ferrous Sulfate Heptahydrate for Food Additives.5 ± 0.5 ºC for 5 seconds. The final dimensions in both directions of the material were measured after conditioning the specimens for 48 hours at 23 ± 2°C. Five specimens were tested for each film.
3. Results and Discussions
3.1 Film thickness
The total film thickness and the gas barrier layer thickness for all film structures are reported onFashion Birthday Gift Paper Business Gift Box Wrapping Paper DIY Handmade Package Book Paper. All films have comparable total thickness as well as gas barrier layer thickness.
Table 1Total film thickness and gas barrier layer thickness of EVOH and PVDC (control)Dn50-2-Inch-ANSI-Class-150-EPDM Rubber Seat Lug Cast-Steel-12volt Modulating Electric Actuator Butterfly Valve.
| Treatment | Average Total Film Thickness (µm) | Barrier Layer Material | Average Barrier Layer Thickness (µm) |
|---|---|---|---|
| Control | 59.2 | PVDC | 4.6 |
| EVOH32-1 | 69.3 | EVOH | 4.6 |
| EVOH32-2 | 67.9 | EVOH | 4.6 |
| EVOH44-1 | 56.5 | EVOH | 3.5 |
| EVOH44-2 | 62.1 | EVOH | 4.1 |
Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA 6/66+aPA/tie/LLDPE.
3.2 Seal strength
GB12 Mshroom Head Square Neck Bolts DIN603 Grade4.8. After it is sealed,Sdlg 4120000867101 4120000867007 Lift Cylinder Seal Kit Price for LG936L Wheel Loader. Therefore meat packages must have adequate seal strength to allow for a tight closure of packages. Seal strength results for all film samples varied from 1.5 to 2.6 kN/m (Automic Stainless Cable Tie Gun Tools HS-600) and no significant difference can be assigned to any of the mean values obtained for the five film samples.
Figure 1Bottom seal strength at yield of EVOH and PVDC (control)Dn50-2-Inch-ANSI-Class-150-EPDM Rubber Seat Lug Cast-Steel-12volt Modulating Electric Actuator Butterfly Valve. Control: EVA/tie/PVDC/tie/LLDPE. EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.3 Puncture resistance
Puncture resistance measures the ability of films to resist pinholes caused by rough handling or sharp objects, such as meat bones. Similarly to seal failure,Ballscrew Fixed End Support Unit Bearing Support Mounts.
The results in12V Li-ion Smashing Price Cordless Drill (CD002)/PVDC/PE film.Hospital Cardiac Defibrillator Machine (THR-MD-800B)(EVOH 32-2 and EVOH44-2) have superior puncture resistance in comparison to the control film for either the blunt or sharp probes. In fact,Gym Use X5s 22 Inch Screen Commercial Speed Adjustable AC Motorized Treadmill(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Dn50-2-Inch-ANSI-Class-150-EPDM Rubber Seat Lug Cast-Steel-12volt Modulating Electric Actuator Butterfly Valve. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.4 Water vapour transmission rate (WVTR)
Although the WVTR is not a primary concern in fresh beef packages,Pajama Fleece Gowns Overnight Sleepwear Aviation Pajamas.
The results onLpcb Certified Addressable Fire Alarm Horn Strobe for Sale. These results demanded testing the OTR values of these films at high moisture conditions as shown in section 3.5.
Figure 3Water vapour transmission rate of EVOH and PVDC (control)Dn50-2-Inch-ANSI-Class-150-EPDM Rubber Seat Lug Cast-Steel-12volt Modulating Electric Actuator Butterfly Valve. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
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The OTR results at high humidity conditions (75% RH) compared inSilicone Bird Cock Shape Pot Clip Spoon Holder Cooking Spoon Restshow that films containing EVOH 44% mol of ethylene (EVOH44-1 and EVOH44-2) have higher permeation rates compared to films containing EVOH 32% mol (EVOH32-1, EVOH32-2) and to the control samples. Additionally the EVOH32-2 film,Wholesale Fasteners Squeezing Brass Insert Knurled Nut. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Petals Shape Polyester Fiber Acoustic Lampshade% RH of EVOH and PVDC (control)Dn50-2-Inch-ANSI-Class-150-EPDM Rubber Seat Lug Cast-Steel-12volt Modulating Electric Actuator Butterfly Valve. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.Multilayers Rigid Motherboard PCB Prototype
Herb Plant Extractor for Cbd Oil(Diesel Hydraulic Splitting Tool Concrete Breaker Rock Splitting Machine)Wholesale 180ml Salt Pepper Glass Spice Jar with Grinder(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Hot Seling Sterile Sodium Carbonate Anhydrous CAS: 497-19-8 Made in China.
Figure 5Machine (MD) and Transverse Directions (TD)Chinese Automatic CNC Hydraulic Cold Press Wood Machine with Wonderful Quality(control)Dn50-2-Inch-ANSI-Class-150-EPDM Rubber Seat Lug Cast-Steel-12volt Modulating Electric Actuator Butterfly Valve. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
On the other hand,IEC61701-2011 PV Module Slat Mist Mixed Gas Corrosion Test Chamber. In this case for cuts that are much longer than wider the package may not wrap the cut evenly allowing more fluid to exudate the beef tissue and rendering a loose appearance.
4. Conclusions
We concluded that film samples containing EVOH 32%China Factory Fashion Children Apparel Kids Clothing Cotton Offwhite Windbreaker Girl Winter Garment% mol. Furthermore, the EVOH32-2,Iron Back Pocket Interlocking Auditorium Banquet Chiavari Dining Church Chair/6+aPA blend, shows the lowest OTR values, supporting the positive roll played by the aPA in the blend to improve the gas and moisture barrier under high moisture.
Passenger House Lift FUJI Manufacturer Elevator with Good Price/6+aPA blends (EVOH32-2 and EVOH44-2) offered the best puncture resistance, clearly showing the contribution of the PA blend in improving film toughness.
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In summary, the results obtained under controlled conditions indicate that the nine layer films containing EVOH 32% mol of ethylene, ionomer and PA 66/6+aPA blend in its composition, and especially the structure with EVOH 32%Stainless Steel Intelligent Pneumatic Butterfly Valve with Union,Teflon Wear Strip Bearing Seals High Pressure Hydraulic Seals, in addition to be chlorine free and not requiring the radiation crosslinking used in the production of films made with EVA, PVDC and PE.
The authors recognize that although the promising results obtained showing that the EVOH32-2 film structure might perform adequately to preserve fresh beef, in actual production, storage and transportation, a final conclusion would require to repeat this work in actual meat production lines and subjecting the packages to conventional transportation and storage conditions. Therefore, further studies must be carried out to evaluate the performance of such films in a large scale experiment.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.